Centralized mouse repositories

Because the mouse is used so widely for biomedical research and the number of mouse models being generated is increasing rapidly, centralized repositories are essential if the valuable mouse strains and models that have been developed are to be securely preserved and fully exploited. Ensuring the ongoing availability of these mouse strains preserves the investment made in creating and characterizing them and creates a global resource of enormous value. The establishment of centralized mouse repositories around the world for distributing and archiving these resources has provided critical access to and preservation of these strains. This article describes the common and specialized activities provided by major mouse repositories around the world.

Spontaneous firing in C-fibers and increased mechanical sensitivity in A-fibers of knee joint-associated mechanoreceptive primary afferent neurones during MIA-induced osteoarthritis in the rat

OBJECTIVE

Osteoarthritis (OA) pain mechanisms are poorly understood. We used the monosodium iodoacetate (MIA) model of knee OA to characterize changes in excitability during the course of OA in different classes of mechanosensitive afferents projecting to joint-associated tissues, and examine whether these afferent responses and pain behavior are correlated.

METHODS

Rats were injected intra-articularly with MIA (1mg in 50 μl). Hind-limb weight bearing was studied 3 (MIA3) and 14 (MIA14) days after MIA, followed by deep anesthesia and teased-nerve-fiber recordings. Spontaneous activity (SA) and mechanically evoked responses of A- and C-mechanosensitive fibers (AM and CM respectively, probably nociceptive) innervating tissues associated with the ipsilateral knee joint were examined.

RESULTS

MIA3 and MIA14 rats exhibited reduced ipsilateral weight bearing. SA (>0.02 impulses/s) occurred in ∼50% of CMs from MIA rats vs 0% in normals. SA firing rates in CMs were significantly higher than normal; decreased weight bearing was correlated with increased CM SA rates. Neither percentages of AMs with SA (20%) nor their firing rates (0-0.01 impulses/s) significantly increased after MIA. In contrast, in MIA rats AMs, but not CMs, exhibited decreased mechanical thresholds and increased firing rates in response to suprathreshold mechanical stimulation.

CONCLUSIONS

These findings of increased SA firing rate in CMs but not AMs and increased mechanical sensitivity of AMs, but not CMs, have not previously been reported. These are two distinct important physiological mechanisms that may underpin spontaneous pain (CMs) and stimulus-evoked pain (AMs) in OA. Our data contribute to a mechanism-based understanding of OA pain.

Risperidone and weight change in children with learning disability. A retrospective study

Aim

Risperidone has been recommended for the management of disruptive behaviour disorders in children with learning disabilities. This study explored the effects of Risperidone on absolute body weight in children with learning disabilities who received Risperidone for disruptive behaviour disorders.

Methodology

Data was collected for children (n = 70) with learning disabilities who were prescribed Risperidone for disruptive behaviour disorders in out patient clinic. Weight, height and BMI were recorded at the first appointment and at the follow up for up to one year. Data was analysed to find any changes in weight and BMI during the course of treatment with Risperidone.

Results

Mean weight gain for the sample was 6.1 kg (sd = 2.7), 1.7 kg more than expected in one year which was statistically significant (t = 6.2, df = 69, p < 0.001). Mean BMI change was 1.51 kg; significantly larger than the mean expected BMI change of 0.62 of this sample (t = 4.98, df = 1.6, P = 0.001). Change in BMI was more for girls, 2.17 (sd = 1.00) compared with boys 1.36 (sd = 1.18), but this was not significant (t = 1.90, df = 49, p = 0.06). There is no significant relationship between Risperidone dose and weight gain (Pearson's r = 0.21, p = 0.42) and BMI (Pearson's r = 0.03, p = 1.00).

Conclusion

Risperidone should be used with caution in children where weight gain could have long lasting impact. Prescribing clinicians should obtain baseline measures of weight, height, BMI and monitor them at regular intervals. Emphasis should be placed on life style interventions such as diet, physical activities etc. Further comparable studies with larger sample sizes using more homogenous diagnostic samples are needed.

Levels of phosphorylated axonal neurofilament subunit H (pNfH) are increased in acute ischemic stroke

For the study of stroke outcomes, there is the need for measurements of severity of stroke damage. Phosphorylated neurofilament heavy protein (pNfH) levels are elevated in axonal injury. We have measured levels of pNfH in stroke and correlated these levels with measures of stroke severity. Blood samples were collected from 54 ischaemic stroke patients at day 1, week 1 (days 7-10) and weeks 3-6, and an ELISA was used to measure pNfH levels in each patient at each time-point. Serum pNfH levels were significantly elevated in stroke patients compared to healthy controls. The levels were low at day 1, higher at day 7 and reached a peak at week 3, the latest day that we assessed. Significant associations were found between the pNfH levels at week 3 and early and stroke severity, size and outcome. Blood pNfH levels that reflect the severity of ischaemic stroke, are correlated with outcome and rise during the weeks after stroke. This may be a useful measure of tissue damage in stroke.

Exploring beyond viral load testing for EBV lymphoproliferation: role of serum IL-6 and IgE assays as adjunctive tests

We examined serum IL-6 and IgE assays as adjuncts to VL monitoring for PTLD. Paediatric solid organ transplant recipients were followed with VL monitoring. VL, IL-6, and IgE assays were compared between PTLD cases and non-cases at <3, 3-6 and >6 months after transplantation. Median IL-6 levels in PTLD cases were 15.5 (2.0-87.1) and 23.3 (2.1-276) pg/mL compared with 3.25 (0.92-114) and 3.5 (0.75-199.25) pg/mL in non-cases at 3-6 and >6 months, respectively (p = 0.006 and p = 0.005). At >6 months, IL-6 levels correlated with VL and PTLD occurrence (Spearman's coefficients = 0.40; p = 0.001 and 0.32; p = 0.003) in univariate analyses. No benefit was derived from performance of IgE levels. The sensitivity and specificity of high VL as a test of PTLD were 76.3% and 92.5%, while the negative predictive value and PPV of VL were 94.9% and 68.4%, respectively. Combining elevated IL-6 with high VL increased the PPV and specificity to 80% and 96.2%, respectively, and improved the receiver operating characteristic curve. Serum IL-6 levels can improve the clinician's ability to identify PTLD, among patients with elevated EBV viral loads.

Genetic contribution to the relationship between personality and depressive symptoms among older women

BACKGROUND

Prior studies suggest that certain types of personality are at higher risk for developing depressive disorders. This study examined the relationship between old age depressive symptoms and two middle-age personality dimensions, neuroticism and extraversion.

METHOD

The present study is part of the Finnish Twin Study on Aging, where altogether 409 female twins who had completed the Eysenck Personality Inventory at the age of 38-51 years were studied for depressive symptoms 28 years later using Center for the Epidemiologic Studies Depression Scale. Logistic regression analysis suitable for dependent data and univariate and Cholesky models for decomposing the genetic and environmental factor were used.

RESULTS

Middle age extraversion protected from later depressive symptoms while neuroticism increased the risk. Twin modeling indicated that the association between neuroticism and depressive symptoms resulted from shared genetic risk factors common to both traits. However, a substantial proportion of the genetic vulnerability was specific to old age depressive symptoms and was not shared with neuroticism. Middle age extraversion had no genetic relationship with old age depressive symptoms.

CONCLUSIONS

The relationship between middle age neuroticism and old age depressive symptoms is strong but only partly the result of genetic factors that predispose to both neuroticism and depressive symptoms. Extraversion, by contrast, has no genetic relationship with depressive symptoms experienced in old age.

Pediatric antifungal therapy. Part I: focus on febrile neutropenia, invasive aspergillosis, combination antifungal therapy and invasive candidiasis in immunocompromised pediatric patients

The number of available antifungal agents has significantly increased in recent years. These agents are starting to take over niches that were previously occupied by conventional amphotericin B. For many of these agents, pediatric data from randomized trials are generally lacking and clinicians are faced with extrapolating from data generated in adult patients. This notwithstanding, this report summarizes recommendations that define the roles of newer antifungal agents in the treatment of selected scenarios among immunocompromised pediatric patients. The report includes the outcome of a Canadian conference on the use of antifungal agents in children, supplemented by literature reviews and incorporating information from existing national or international guidelines, where appropriate. The focus of the report is on febrile neutropenia, invasive aspergillosis, combination antifungal therapy and selected aspects of the management of invasive candidiasis.

Pediatric antifungal therapy. Part II: neonatal infections

The management of neonatal fungal infections poses several challenges, including the fact that the choices of available agents are limited, given the paucity of data relating to the use of newer antifungal agents in the group of infants. The information summarized herein represents in part the consensus of a group of clinicians involved in the care of neonates at risk of and with fungal infections. The document addresses the prophylaxis and treatment of fungal infections in neonates. It highlights the role of current and emerging antifungal agents, including the lipid amphotericin B products, echinocandins and triazoles.

Induction of inflammatory bowel disease in immunodeficient mice by depletion of regulatory T cells

The severe combined immunodeficiency (SCID) model of colitis shares many features of idiopathic inflammatory bowel disease (IBD) in humans. The SCID model is highly reproducible and easily manipulated, and as such provides a useful tool for studying mucosal immune regulation as it relates to the pathogenesis and treatment of IBD in humans. This unit describes a cell transfer system in which SCID mice are reconstituted with CD4(+) CD45RB(high) cells to induce IBD. The CD4(+) cells are isolated by immunomagnetic negative selection using monoclonal antibodies, and are then separated by fluorescent cell sorting into CD45RB(high) and CD45RB(low) cells. The former population reproducibly induces disease in recipients. A support protocol describes methods to monitor disease progression, which is characterized by weight loss, loose stools, and histologically assessed lesions in the colon.

Designing Organizations that Design Environments: Lessons from Entrepreneurial Expertise

Human artifacts lie on the interface between their inner environments and their outer environments. Organizations, therefore, are apt subjects to be studied through a science of the artificial. Furthermore, organizational design happens at two interfaces: first, at the interface between organizational founder(s) and the firms they design, and second, between the firms and the environments in which they operate. We use recent developments in the study of entrepreneurial expertise to show why an effectual logic of design is necessary at the first interface, and what its consequences are for designing at the second. In particular, we use the exemplar case of Starbucks to codify three key characteristics of the design problem at the first interface — namely, Knightian uncertainty, goal ambiguity and environmental isotropy. We then use an `alternate histories' method to trace four strategic options — namely, planning, adaptation, vision and transformation — for designing at the second interface. In the final analysis, organizational design is important because effectuators using transformational approaches not only design organizations, but concurrently end up designing the environments we live in.

SOX2 anophthalmia syndrome: 12 new cases demonstrating broader phenotype and high frequency of large gene deletions

BACKGROUND

Developmental eye anomalies, which include anophthalmia (absent eye) or microphthalmia (small eye) are an important cause of severe visual impairment in infants and young children. Heterozygous mutations in SOX2, a SOX1B-HMG box transcription factor, have been found in up to 10% of individuals with severe microphthalmia or anophthalmia and such mutations could also be associated with a range of non-ocular abnormalities.

METHODS

We performed mutation analysis on a new cohort of 120 patients with congenital eye abnormalities, mainly anophthalmia, microphthalmia and coloboma. Multiplex ligation-dependent probe amplification (MLPA) and fluorescence in situ hybridisation (FISH) were used to detect whole gene deletion.

RESULTS

We identified four novel intragenic SOX2 mutations (one single base deletion, one single base duplication and two point mutations generating premature translational termination codons) and two further cases with the previously reported c.70del20 mutation. Of 52 patients with severe microphthalmia or anophthalmia analysed by MLPA, 5 were found to be deleted for the whole SOX2 gene and 1 had a partial deletion. In two of these, FISH studies identified sub-microscopic deletions involving a minimum of 328 Kb and 550 Kb. The SOX2 phenotypes include a patient with anophthalmia, oesophageal abnormalities and horseshoe kidney, and a patient with a retinal dystrophy implicating SOX2 in retinal development.

CONCLUSION

Our results provide further evidence that SOX2 haploinsufficiency is a common cause of severe developmental ocular malformations and that background genetic variation determines the varying phenotypes. Given the high incidence of whole gene deletion we recommend that all patients with severe microphthalmia or anophthalmia, including unilateral cases be screened by MLPA and FISH for SOX2 deletions.

The process of systematic review and its application in agri-food public-health

Foodborne illness is an important public-health concern. Livestock operations represent the original source of many foodborne pathogens. Policy- and decision-makers in the area of agri-food public-health need dependable information on interventions to reduce foodborne diseases. While individual studies might be weak or reach contradictory conclusions, the body of information contained in all studies might reveal a clearer picture of the state of knowledge. A formal process has been developed for conducting systematic reviews of the human healthcare literature. Systematic reviews differ from traditional narrative reviews in that systematic reviews follow a structured research protocol to reduce sources of bias at all stages of the review. This includes the objective, the literature search, the identification of relevant literature, quality assessment of relevant studies, summarization or statistical analysis of data, and conclusions. To date, systematic reviews have not been widely used in agri-food public-health. Existing systematic reviews on agri-food public-health topics revealed a scarcity of rigorously conducted intervention research, indicating a need for additional high quality primary studies. The specific protocols used to conduct systematic reviews in agri-food public-health need to accommodate the use of challenge studies and observational studies, the lack of randomized controlled trials, and the clustering of animal populations.